Oily cosmetics are used for the purpose of softening or protecting the skin, hair, or the like. Particularly, solid type oily cosmetics are easily applied and are conveniently carried. Therefore, the solid type oily cosmetics are applied to cosmetics for various applications including makeup cosmetics such as lipstick, foundation, and blush, skin care cosmetics such as eye cream, antiperspirant, and solid perfume, and hair cosmetics such as hair dressing agents.
Oily cosmetics which are formed in a stick shape and are stored in an extension type container are used in an eyebrow pencil, eyeliner, eye shadow and the like. Oily cosmetics which are melted, filled in an inner tray of a compact, cooled, and solidified are used as foundation and the like. In some cases, pigment powder is blended with these oily cosmetics as a coloring agent. However, when the oily cosmetics are heated and dissolved so as to be in a liquid phase in the process of filling a stick type container or an inner tray container with the oily cosmetics, in some cases, the pigment powder aggregates to form a striped pattern or the like, thereby impairing the appearance. Particularly, pigment powder is blended in a high concentration in order to increase coloring power in an eyebrow pencil, eyeliner, and the like, and therefore, it is difficult to obtain fluidity of the oily cosmetics during heating and dissolving. Thus, in some cases, it is difficult to fill a container with the oily cosmetics. In addition, the oily cosmetics with which the powder is highly concentrated tend to be hard to use.
A method for adjusting oily components (for example, following Japanese Unexamined Patent Publication No. 2014-189497) or a method for modifying a lipophilic treatment agent on the surface of powder is known as a method for improving dispersibility of powder in oily cosmetics. It is also known that the properties of the treatment agent regarding the coated powder are expressed while using the cosmetics (for example, Japanese Unexamined Patent Publication No. 2002-322015 and Japanese Unexamined Patent Publication No. 2010-77111). In addition, a method for making powder highly functional by coating the powder with a combination of a plurality of surface treatment agents has also been proposed (for example, Japanese Unexamined Patent Publication No. 2013-79264).
However, the oily cosmetics in the related art fail to achieve all of the desired characteristics of fluidity, color uniformity, and usability at a high level in the same cosmetic product. For example, some prior art oily cosmetics do not have sufficient viscosity or fluidity during the heating and melting steps of manufacturing, while other prior art oily cosmetics fail to adequately suppress color floating problems due to the aggregation of powder. Still other prior art oily cosmetics exhibit usability problems such as greasy feeling and insufficient coverage due to clumping. Therefore, further improvement is required.
The present invention has been made in consideration of the above-described circumstances, and an object of the present invention is to provide oily cosmetics which exhibit sufficient filling properties of viscosity and fluidity during heating and melting, such as when preparing the oily cosmetics to be filled into a mold or container. Additionally an object of the invention is to significantly ameliorate the problems associated with the aggregation of powder, and to provide oily cosmetics with excellent usability characteristics.